Estimation of air-sea carbon flux in the Western Arctic Ocean using in-situ and remotely sensed data

Affected by global warming and rapid sea ice change, the Western Arctic Ocean is a strong potential carbon sink. In order to get a high resolution basin-scale estimate of the air-sea flux of CO₂ and carbon uptake in the Western Arctic Ocean from 180°E to 135°W, 65°N to 85°N, we applied an extrapolation method. Empirical relationship between marine partial pressure of carbon dioxide (pCO₂ ^sw), Sea Surface Temperature (SST) and salinity were derived from underway measurements collected during the 3^rd CHINARE, in August 2008. pCO₂ ^sw was computed from remotely sensed SST, and salinity produced by remotely sensed Colored Dissolved Organic Matter (CDOM). Air-sea CO₂ flux was calculated from the air-sea difference of pCO₂ and remotely sensed wind speed. Results showed that in August, 2008, the monthly CO₂ flux was highest in the Chukchi Sea, secondly in the Beaufort Sea and then in the Canada Basin. In August, the Western Arctic Ocean was a net atmospheric sink for CO₂ and carbon absorption was 4.8 TgC.